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A test of the B&M Luxos U on the Shenandoah 1200

I just completed the Shenandoah 1200 with the B&M Luxos U. Riding time was roughly 4am to 10pm the first day; 2am to 10pm days two and three and 1am to 12:30 pm day four. Of course rolling time is actually shorter than that, considering stopped time at Controls etc.

The Luxos U replaced a two-light headlight setup that I had before, the Inoled 10+ and Edelux.

I liked the Inoled for its wide lane-filling beam and the Edelux for its bright spot that I had focussed further out. Either would be slightly brighter by itself but I liked the setup.

The key feature of the Luxos U, for me, was the USB charging “station” on the wired remote control. I ride with a Garmin 705 and enjoy having the backlight on 24×7. To accomplish that, I have been using a Gomadix 4xAA charger, always connected, swapping the AA batteries old for fresh, every 24 hours. I figured that with the Luxos, I wouldn’t need batteries anymore, one less thing to pack in my drop bags.

I mounted the Luxos at my front caliper with the included bracket. I had the old lights mounted on the handlebars so the new mount location also gave me some more room for my hands. That’s a good thing too!

The remote is mounted on the top tube with cable ties. A USB cord is connected and runs forward to the Garmin 705. Because the instructions that came with the Luxos said that the USB charging station shouldn’t be used in the rain, I put part of a ziploc bag over it, tightly tied to the two cords with electrical tape. I can see through the plastic to the indicator light on the remote that shows that the USB connection is live and I can operate the remote to turn the headlight on.

I also use a wired taillight. Yes, there are a lot of wires! I have to do a better job tying it all down neatly, now that I’m happy with the setup.

I’ll post some pictures when I get a chance.

So … in action …

The light is great. It’s very wide, the bright and lengthy beam nicely replace my previous setup. The Garmin stays fully charged, mostly, but I’ll get to that. I really couldn’t see the light adjusting itself to my speed, but wasn’t really looking for that. It’s supposed to focus light closer when you’re going slowly, further at speed, but perhaps it’s subtle. It’s probably easier to measure and detect on a stand than when riding.

The light has a built-in rechargeable battery that stays charged as long as you are maintaining enough speed. If the charge drops below some level, the electronics in the light turn off the USB charging function. The electronics favour the standby light when you’re stopped, turning off the USB rather than sacrificing the light.

During the day, for a short stop like a traffic light, the battery in the light keeps the USB charger active the entire time. Stopping at a Control, I’d come back to the bike and see the “external power lost” message on the Garmin, but that would disappear immediately upon starting to roll again. The Garmin stays fully charged during the day.

At night, with the headlight (and taillight) left on, the “power lost” message comes much quicker — not for the duration of a traffic light though. That’s assuming that the light’s internal battery has been kept charged by riding at a speed greater than 12mph/20kph. That seemed to be the point at which the output from the Schmidt hub (mine’s what they now call the Classic) would keep the headlight and taillight at full brightness and the USB charging station live. For short periods of time below that point, the USB charger would stay on. For longer periods, it would turn off and on as I crossed that threshold.

Below 6mph/10kph, the headlight would flicker if I had been riding slowly enough before that to deplete the light’s internal battery. On the 8-9 mile climb out of Mt. Airy back up to the Blue Ridge Parkway, and the switchback climb up the Edinburg Gap, the headlight’s battery was depleted and I would notice the flickering every time my speed dropped. During that time, I’d have the external power lost message on the Garmin and as a result, the backlight would go off. These were climbs in the dark; during the day even low speed would keep the USB charger alive.

I didn’t run the light during the day. It has a daylight sensor and produces a diminished light during the day but I didn’t use that. I expect that with the daytime light on, and the taillight, there might be some speed below which the USB charging would stop after depleting the internal battery. I also have two Cateye battery taillights mounted vertically on my rack (like seatstays) that I leave flashing during the day. They can be seen for longer distances than the wired taillight. At night, riding with others, I’ll leave those on steady; by myself, they’ll be on flash.

I also did not use the floodlight function of the light. If I recall correctly, the light output is 70 lux normally and 90 lux with the floodlight. The floodlight will run until the battery is depleted, apparently, and no doubt will shut down the USB charging at some point.

All things considered, I’m very happy with the setup. Since the Garmin’s own battery life is something like 12 hours, there’s never going to be a problem with it running out of juice. I cannot imagine riding at less than 12mph/20kph for 12 hours in a row in the dark! If I was touring perhaps, pulling a trailer, but then I’d not likely be riding in the dark.

With the USB charging station sealed against moisture, I cannot swap my cell phone USB cord at the charging station if I wanted to charge that instead of maintaining the Garmin charge. I have a little dongle that adapts the mini USB connector that works with the Garmin 705 to a micro USB connector (I think that’s what the two are called). I’ll probably carry that in the future and try charging my cell phone, see how that works.

The speeds that I mention are approximate. I’m sure that they’ll vary with the hub output and would be different without the wired taillight. It would be interesting to put the bike on powered rollers and test all combinations…

Thank you for a great article on the use of the Luxos U. I’ve been riding it now for several months and love it. The only issue I’ve had is getting the “floodlight” to stay on or come on. When I first installed the light it worked great, then it stopped staying on. It would flash, but not stay constant. I wrote Peter White for his opinion, waiting response today. Anyway, I use the light 24×7 day and night. The charging function is outstanding, using it to power the Garmin 705 Edge, IPOD, and Tracphone. It is so nice to have that capability on tour. Cheers